The present invention relates to a fire extinguishing system for automatically discharging a predetermined amount of extinguishing agent and then, if necessary, repeating the discharge cycle until the fire is extinguished. The system is then reset and available for automatically extinguishing further fires.
A fire may be extinguished by various well known methods including cooling the burning materials, blanketing the fire with inert gas, inhibiting the combustion process with appropriate chemicals and using solid particles or the like to prevent access of air. Fire extinguishing system use one or more of these methods with the exact method employed depending upon the nature of the fire. Water is one of the most effective cooling agents used in fire extinguishing systems and may include wetting agents for added penetration and forming agents for exclusion of air and to help cool the burning materials. However, there are many fires on which water should not be used and on which dry extinguishers and the like are preferred. The typical dry extinguisher comprises a dry powder consisting principally of sodium bicarbonate which generates carbon dioxide, cools the burning materials, and prevents access of air.
Fire extinguishing systems employing water, dry chemicals and the like as extinguishing agents normally require a propellant for delivering the extinguishing agent to the hazard area. The propellant may be generated when needed or stored in a separate container. Also, the extinguishing agent may be pre-pressurized by storing the propellant with the extinguishing agent in the same vessel. Fire extinguishing systems have been developed using this pre-pressurized or stored pressure concept in which mechanical or electrical means, activated by a rise in temperature, have been used to rupture or mechanically open the valve of the stored pressure container thereby delivering the extinguishing agent to the hazard area. However, these systems have no means for automatically discharging only a pre-determined amount of extinguishing agent and then, only if nencessary, repeating the discharge cycle until the fire is extinguished. Accordingly, these systems have many disadvantages including the delivery of excess extinguishing agent to the hazard area which wastes valuable chemicals and may result in unnecessary damage to materials stored in the hazard area by the excess extinguishing agent.
Fire extinguishing systems typically employ a delivery hose connected directly to the extinguishing agent vessel and a manaully operated discharge valve at the end of the delivery hose. This arrangement requires the operator to use both hands to hold the delivery hose and to operate the discharge valve. Also, systems of this type do not provide for automatic purging of the delivery hose and accordingly the delivery hose must be manually purged or otherwise the delivery hose may become stopped up and the system rendered inoperative.
In view of the foregoing, an object of the present invention is to provide an improved film extinguishing system.
A further object of the present invention is to provide a fire extinguishing system which automatically delivers a predetermined amount of extinguishing agent to the hazard area.
A still further object of the present invention is to provide a fire extinguishing system which automatically discharges a pre-determined amount of extinguishing agent and then, if necessary, repeats the discharge cycle until the fire has been extinguished.
A yet further object of the present invention is to provide a fire extinguishing system which automatically delivers a predetermined amount of extinguishing agent or demand and then resets so that it is available for automatically extinguishing further fires.
Yet another object of the present invention is to provide a fire extinguishing system in which the delivery hose is easily purged, either manually or automatically.
Still another object of the present invention is to provide a fire extinguishing system which is simple in construction, easy to manufacture and reliable in operation.
Still further objects of the present invention will become apparent upon reading the following description taken in conjunction with the appended claims.